Madeleine Stowe teased that we'll see more of Victoria's past, mainly her decision to betray David. "You're going to find out Victoria never really understood why she did what she did and it's actually very obvious because Conrad was involved with terrorists and Victoria knowing this, had to choose between her lover or her son's life."
"She has a lot of interesting paths, a dramatic history, that hasn't actually come to the fore yet," she said about Victoria. "Probably more will come...She had a very demented early background, very tortured and had been used over and over and over again and I think Emily and Victoria are very similar creatures."
Stowe also said she thinks the series could have ended with the Season 3 finale, sentiments her costar Emily VanCamp (Emily Thorne aka Amanda Clark) also shared.
"I think they ended it very well last season," she told E!. "But I think that they feel there's much more to reveal and if the network will go with it, as they've somewhat promised, you're going to find that maybe what Emily believes to be true is not the whole truth."
Stowe told E! that she's not sure what direction the show is headed in this season, but she can "guarantee...that you'll be very surprised. I will say that it appears that David and Victoria have some sort of sadomasochist relationship."
Source 1 and 2.